British get a Merlin engine P-39

Packard began producing Merlin engines in September 1940. This is the same month the British purchasing commission ordered their P-39's. Let's say the commission tells Bell to fit the Merlin rather than the Allison engine to their planes. While this requires some small adjustments to the design, such as the air intake having to be on the bottom of the fuselage rather than the top, Bell makes these and Packard supplies the engines.

The P-39's arrive in England and are capable of maintaining a speed of 370 - 400 mph up to about 20,000 feet (early Merlin), maybe 25,000.

Instead of the P-39 being a dog over 15,000 feet, it's now a competitive fighter. The USAAF sees this and orders some for themselves once the US enters the war (as they did with the P-40).

While most P-39 retain an Allison engine, those with a Merlin in the Pacific prove to be far more useful defensively against the Japanese. The US still gives the Allison version to the Russians as well.

The P-39 never gets the reputation of being awful.

 

Hmmm...to be continued



As you know the engine is seated behind the pilot connected by a shaft that a cannon was fired through also..."the P-39 design was handicapped by the absence of an efficient turbo-supercharger, preventing it from performing high-altitude work." - The Merlin may have helped with that...BUT...Merlins were not being produced in enough numbers to service ALL aircraft (Britain would have had most of its bomber fleet with merlins if possible. - Had to use the radial (Bristol Hercules)
So, its success is really due to the Soviet use, as the allies tended to use it for ground pounding. Aircraft like the Westland Whirlwind ( a beautiful aircraft) couldn't get a look in for Merlins instead relying on the lesser rated Rolls Royce Peregrines - With the Hurricanes, Spitfires, Mosquitos and Lancasters especially eating up the supply for Merlins...Other engines had to be used - And Britain could not supply the US with Merlins so Packard took up the challenge - And im sure the US had the same thing going on...Not enough for all their aircraft so concentrated their engines on "their best ariframe" - P-40s etc getting Allisons...
In my opinion the P-39 was an unusual design that was effective but not superior to other US airframes...The P-40 and 39 got Allisons - P-47 got the very reliable radials.
The US treated this aircraft like it did the P-40 - A second string fighter used in training units and for lend lease (think the F-16 as a more modern example - a good fighter but not good enough for Western Airforces front line).
"The P-39 used the V-1710 with remote reduction gear. There was no such Merlin in production, meaning that Merlin-powered P-39 was impossible ..."

 

They could be tricky to fly. Power spin to the right, no problem. But power spin to the left and you could spin all the way down to mother earth. Trick was to reduce the throttle to regain control.

See Mozart Kaufman's Fighter Pilot, pages 23-4.

<--- not a pilot and I just read books.

 

Not completely true. The P-40F and K were both Merlin engine airplanes and built in some quantity. They saw extensive service in the MTO and considerable service in the PTO. Both were used as frontline fighters and performed well in that role.
The big reason the P-39 got short shrift in the USAAF was because it had too short a range. Not a problem for the Russians, but the US simply couldn't use a short-range fighter where they needed one that could escort bombers long range and the more range a plane had the better.

 

The Merlin engine did much to overcome the limitations imposed by the Allison, and a total of 1311 examples powered by the American-made version of the Merlin built by the Packard Motor Car Company were ordered under the designation P-40F.
My Avatar scored most of his kills in a P-40 (22 Kills) - Its perhaps pilots like him that made the P-40 look a little better than it was - (Buffalo for example relied on good pilots to get performance/kills out of it) - I agree the P-40 was a pretty decent aircraft...But still an old airframe. Pretty much any aircraft would be better with a Merlin installed.
It was still used as a second string aircraft - The Australians used them (to good effect) only because newer Spifires/Mustangs etc weren't available.
With some structural changes the P-40 may have gone on to bigger and better things...
With some changes...

Notice the clipped wings for low altitude performance.
Not really a chance in Europe against an advanced 109 or the FW190 - The P-40 was used to good effect in North Africa and China...

 

Clive Caldwell (my avatar) standing in front of the group with pipe and the Australia North African P-40



Australian P-40N "Currawong"


Dick Cresswell with his P-40E

 

Obvious question - why? Did Packard on its own take interest in producing a promising new engine? Did the British ask them to, and if so what were their intentions? Put them in the American aircraft they were acquiring, as was eventually done in the P-40? Did they think at that time to use the Packard Merlin in the new fighter they had ordered from North American? Or was the intent to ship Merlins to Britain for RAF use?

 

Because it was an alternative to license producing the Allison, among other things. The main reason was Rolls Royce asked Packard to produce the engine because they themselves didn't have the capacity to meet British demand. Packard, agreed. Ford had previously rejected a similar proposal from Rolls Royce. Packard also seemed to be the best choice having long experience with manufacturing large V-8 and V-12 engines.

Interestingly, one of the biggest issues Packard had in starting production was devising ways to greatly improve the tolerances on the Merlin engine's parts. The British used hand fitting that didn't work with US mass production systems, so all of the drawings and specifications had to be gone through, and tolerances tightened significantly, to come up with an engine that could be mass produced. Because RR wanted to keep everything standardized across production lines, the US demands for tighter tolerances, along with other suggested changes, resulted in RR upping their tolerances to US standards and producing better, longer lasting, engines.

Of course, none of this would preclude the British Purchasing Commission from asking Bell Aircraft to fit the Merlin in the P-39 months before the US entered WW 2 when the Merlin was considered a 'foreign' design by the USAAC and not being seriously considered for use in their aircraft. It would have been doable, and the first say 100 to 500 P-39 the British would get had the Merlin in them.

Except for the short range of the plane, which probably wasn't a big deal to the RAF, it would have made the P-39 competitive with early Spitfires in performance.

 

Thanks. I understand similar things happened with the Bofors and Oerlikon cannons; adapting them for American methods both simplified production and improved quality.

 

The US deliberately set out to make an aircraft that could match German aircraft over Europe…The P-51 was their answer…One of the lessons gained was the need for an inline engine. The Allison was the American inline…but still didn’t give the performance of the Merlin…
Needless to say the US was very interested in the FW190…A radial!
The Germans made the radial competitive partly by making it smaller and introducing a cowling that negated much of the drag radials create. The Soviets followed suit…